static const float cube_verts[] = {
    // each vertex has X, Y, Z, NX, NY, NZ, U, V
    // front
    -1.25, -1.25,  1.25,  0,  0,  1,   0, 0.5,
     1.25, -1.25,  1.25,  0,  0,  1, 0.5, 0.5,
     1.25,  1.25,  1.25,  0,  0,  1, 0.5,   0,
    -1.25,  1.25,  1.25,  0,  0,  1,   0,   0,
    // back
    -1.25, -1.25, -1.25,  0,  0, -1,   1,   1,
     1.25, -1.25, -1.25,  0,  0, -1, 0.5,   1,
     1.25,  1.25, -1.25,  0,  0, -1, 0.5, 0.5,
    -1.25,  1.25, -1.25,  0,  0, -1,   1, 0.5,
    // left
    -1.25, -1.25, -1.25, -1,  0,  0, 0.5, 0.5,
    -1.25, -1.25,  1.25, -1,  0,  0,   1, 0.5,
    -1.25,  1.25,  1.25, -1,  0,  0,   1,   0,
    -1.25,  1.25, -1.25, -1,  0,  0, 0.5,   0,
    // right
     1.25, -1.25, -1.25,  1,  0,  0,   0,   1,
     1.25, -1.25,  1.25,  1,  0,  0, 0.5,   1,
     1.25,  1.25,  1.25,  1,  0,  0, 0.5, 0.5,
     1.25,  1.25, -1.25,  1,  0,  0,   0, 0.5,    
    // top
    -1.25,  1.25,  1.25,  0,  1,  0,   0, 0.5,
     1.25,  1.25,  1.25,  0,  1,  0, 0.5, 0.5,
     1.25,  1.25, -1.25,  0,  1,  0, 0.5,   0,
    -1.25,  1.25, -1.25,  0,  1,  0,   0,   0,
    // bottom
    -1.25, -1.25,  1.25,  0, -1,  0, 0.5,   1,
     1.25, -1.25,  1.25,  0, -1,  0,   1,   1,
     1.25, -1.25, -1.25,  0, -1,  0,   1, 0.5,
    -1.25, -1.25, -1.25,  0, -1,  0, 0.5, 0.5
};

static const uint16_t cube_indices[] = {
    // triangle list, each triangle has 3 vertex indices
    0, 1, 2,
    0, 2, 3,
    5, 4, 6,
    6, 4, 7,
    8, 9, 10,
    8, 10, 11,
    13, 12, 14,
    14, 12, 15,
    16, 17, 18,
    16, 18, 19,
    21, 20, 22,
    22, 20, 23
};

